1. Field of the Invention
The present invention relates to a humidifier having a controlled airflow pattern. More particularly, the present invention relates to a humidifier having a means to cause the produced vapor/mist to swirl in a vortex as it exits the humidifier.
2. Description of the Prior Art
Humidifiers are useful in raising the humidity of air inside homes, particularly during periods of dry weather during the winter and when heat inside a home causes the relative humidity within the home to be lowered to an uncomfortable level. Under these conditions, it is desirable to introduce moisture into the air. Such increased humidity may be desirable in order to improve the comfort level for individuals experiencing the humidified air. For example, during cold weather indoor humidity levels can drop causing drying of skin or throat and adding to the discomfort of respiratory infections.
In general, humidifiers vaporize water and expel the vapor into the surrounding environment in order to increase the moisture content thereof. Humidifiers are available in a variety of sizes and designs and include both console units and portable units. Console units typically are large stationary units having the humidifying capacity to affect large areas such as an entire house. Portable units are smaller in size and usually have the humidifying capacity to meet the requirements of a single room. Portable humidifiers due to their small size permit them to be moved from room to room as required.
Several types of humidifiers for increasing humidity in a room are well known in the art, and include ultrasonic, steam-type, warm-air and evaporative humidifiers. In each case, such humidifiers typically include a housing having an inlet, an outlet, a reservoir for holding water and a fan that is connected to the housing for creating an airflow. Water is supplied to the reservoir by a supply tank which is removably supported in the housing. The tank may be removed as required in order to replenish the water supply. Water is typically introduced into the tank through a fill hole which is covered by a removable cap.
Water is typically transferred from the tank to the base reservoir through a valve assembly disposed in the bottom of the tank. When the tank is placed in the base, the valve engages a member on the base which urges the valve into an open position thereby allowing the water to flow into the reservoir. As water flows from the tank to the reservoir, air simultaneously is drawn into the tank through the valve by the vacuum created from the exiting water. When the water level in the reservoir rises to such a degree that the valve opening becomes covered with water, a hydrostatic balance is reached and the flow of water ceases. As water is vaporized, the reservoir level drops disturbing the balance and resulting in the continued flow of water from the tank. This controlled flow cycle ensures that the humidification device will have a supply of water with which to vaporize, as well as limiting the amount of water such that no water spills over the edges of the base reservoir.
Ultrasonic or nebulizing humidifiers typically atomize the water by way of an ultrasonic transducer. The transducer converts water in the reservoir to a fine mist by using an ultrasonic wave produced with a vibrating plate or nebulizer contained therein. The resulting fine mist is then typically directed out of the humidifier with a fan to raise the moisture content in the surrounding area.
Steam-type humidifiers, on the other hand, often utilize an induction heating process, which involves the heating of a metal target or work piece by an induced current. Generally, water is provided in a reservoir together with a metal target. An inductor coil adjacent the target is supplied with power causing the target to heat the water sufficiently to produce steam. The steam is directed out of the humidifier into the environment to thereby increase the humidity of the environment.
In evaporative humidifiers, a water absorbing material, generally known as a wick, is seated partially submerged in the water of the reservoir and is adapted to draw water in the upper non-immersed part by capillary action. An airflow created by a fan is directed to pass through the upper non-immersed portion of the wick to humidify the air in the room.
Generally, the primary goal of all types of conventional humidifiers is to provide moisture to the environment with little attention being paid to the manner in which the moisture laden vapor/mist is visually presented. However, in U.S. Pat. No. 5,322,646, a visually entertaining humidifier has been proposed which generates and displays a small scale tornado-like air flow with the vapor/mist produced by the humidifier. This is accomplished with two air distribution tubes mounted within a chamber which provide an airflow to urge a water aerosol into a helical path to simulate a tornado prior to the moisture stream exiting the humidifier. The resulting effect is both visually entertaining and practical in terms of humidifying the surrounding room.
Accordingly, it would be desirable to improve upon the entertaining effect of such humidifiers, while providing a simpler and more cost-effective design. It would be further desirable to provide a device which performs a similar effect, but directs airflow in a more predictable and specific pattern.